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[PATCH 04/11] parse_object: special code path for blobs to avoid putting whole object in memory

From
Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Date
Feb 27, 2012, 07:55 UTC
Message-ID
<1330329315-11407-5-git-send-email-pclouds@gmail.com>
In-Reply-To
<1330329315-11407-1-git-send-email-pclouds@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 object.c    |   11 +++++++++++
 sha1_file.c |   33 ++++++++++++++++++++++++++++++++-
 2 files changed, 43 insertions(+), 1 deletions(-)
diff --git a/object.c b/object.c
index 6b06297..0498b18 100644
--- a/object.c
+++ b/object.c
@@ -198,6 +198,17 @@ struct object *parse_object(const unsigned char *sha1)
 	if (obj && obj->parsed)
 		return obj;
 
+	if ((obj && obj->type == OBJ_BLOB) ||
+	    (!obj && has_sha1_file(sha1) &&
+	     sha1_object_info(sha1, NULL) == OBJ_BLOB)) {
+		if (check_sha1_signature(repl, NULL, 0, NULL) < 0) {
+			error("sha1 mismatch %s\n", sha1_to_hex(repl));
+			return NULL;
+		}
+		parse_blob_buffer(lookup_blob(sha1), NULL, 0);
+		return lookup_object(sha1);
+	}
+
 	buffer = read_sha1_file(sha1, &type, &size);
 	if (buffer) {
 		if (check_sha1_signature(repl, buffer, size, typename(type)) < 0) {
diff --git a/sha1_file.c b/sha1_file.c
index f9f8d5e..a77ef0a 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -19,6 +19,7 @@
 #include "pack-revindex.h"
 #include "sha1-lookup.h"
 #include "bulk-checkin.h"
+#include "streaming.h"
 
 #ifndef O_NOATIME
 #if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
@@ -1149,7 +1150,37 @@ static const struct packed_git *has_packed_and_bad(const unsigned char *sha1)
 int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
 {
 	unsigned char real_sha1[20];
-	hash_sha1_file(map, size, type, real_sha1);
+	enum object_type obj_type;
+	struct git_istream *st;
+	git_SHA_CTX c;
+	char hdr[32];
+	int hdrlen;
+
+	if (map) {
+		hash_sha1_file(map, size, type, real_sha1);
+		return hashcmp(sha1, real_sha1) ? -1 : 0;
+	}
+
+	st = open_istream(sha1, &obj_type, &size, NULL);
+	if (!st)
+		return -1;
+
+	/* Generate the header */
+	hdrlen = sprintf(hdr, "%s %lu", typename(obj_type), size) + 1;
+
+	/* Sha1.. */
+	git_SHA1_Init(&c);
+	git_SHA1_Update(&c, hdr, hdrlen);
+	for (;;) {
+		char buf[1024 * 16];
+		ssize_t readlen = read_istream(st, buf, sizeof(buf));
+
+		if (!readlen)
+			break;
+		git_SHA1_Update(&c, buf, readlen);
+	}
+	git_SHA1_Final(real_sha1, &c);
+	close_istream(st);
 	return hashcmp(sha1, real_sha1) ? -1 : 0;
 }
 
-- 
1.7.3.1.256.g2539c.dirty
Previous: Nguyen Thai Ngoc DuyNext: Nguyễn Thái Ngọc Duy
Message 10 of 48 in “Large blob fixes”
  1. 00/11 Large blob fixesNguyễn Thái Ngọc Duy, Feb 27, 2012
  2. 01/11 Add more large blob test casesNguyễn Thái Ngọc Duy, Feb 27, 2012
  3. Peter BaumannFeb 27, 2012
  4. 02/11 Factor out and export large blob writing code to arbitrary file handleNguyễn Thái Ngọc Duy, Feb 27, 2012
  5. Junio C HamanoFeb 27, 2012
  6. Junio C HamanoFeb 27, 2012
  7. 03/11 cat-file: use streaming interface to print blobsNguyễn Thái Ngọc Duy, Feb 27, 2012
  8. Junio C HamanoFeb 27, 2012
  9. Nguyen Thai Ngoc DuyFeb 28, 2012
  10. 04/11 parse_object: special code path for blobs to avoid putting whole object in memoryNguyễn Thái Ngọc Duy, Feb 27, 2012
  11. 05/11 show: use streaming interface for showing blobsNguyễn Thái Ngọc Duy, Feb 27, 2012
  12. Junio C HamanoFeb 27, 2012
  13. 06/11 index-pack --verify: skip sha-1 collision testNguyễn Thái Ngọc Duy, Feb 27, 2012
  14. 07/11 index-pack: split second pass obj handling into own functionNguyễn Thái Ngọc Duy, Feb 27, 2012
  15. 08/11 index-pack: reduce memory usage when the pack has large blobsNguyễn Thái Ngọc Duy, Feb 27, 2012
  16. 09/11 pack-check: do not unpack blobsNguyễn Thái Ngọc Duy, Feb 27, 2012
  17. 10/11 archive: support streaming large files to a tar archiveNguyễn Thái Ngọc Duy, Feb 27, 2012
  18. 11/11 fsck: use streaming interface for writing lost-found blobsNguyễn Thái Ngọc Duy, Feb 27, 2012
  19. Junio C HamanoFeb 27, 2012
  20. Nguyen Thai Ngoc DuyFeb 28, 2012
  21. 00/10 Large blob fixesNguyễn Thái Ngọc Duy, Mar 4, 2012
  22. 01/10 Add more large blob test casesNguyễn Thái Ngọc Duy, Mar 4, 2012
  23. Junio C HamanoMar 6, 2012
  24. 02/10 streaming: make streaming-write-entry to be more reusableNguyễn Thái Ngọc Duy, Mar 4, 2012
  25. 03/10 cat-file: use streaming interface to print blobsNguyễn Thái Ngọc Duy, Mar 4, 2012
  26. Junio C HamanoMar 4, 2012
  27. Nguyen Thai Ngoc DuyMar 5, 2012
  28. 04/10 parse_object: special code path for blobs to avoid putting whole object in memoryNguyễn Thái Ngọc Duy, Mar 4, 2012
  29. 05/10 show: use streaming interface for showing blobsNguyễn Thái Ngọc Duy, Mar 4, 2012
  30. 06/10 index-pack: split second pass obj handling into own functionNguyễn Thái Ngọc Duy, Mar 4, 2012
  31. 07/10 index-pack: reduce memory usage when the pack has large blobsNguyễn Thái Ngọc Duy, Mar 4, 2012
  32. 08/10 pack-check: do not unpack blobsNguyễn Thái Ngọc Duy, Mar 4, 2012
  33. 09/10 archive: support streaming large files to a tar archiveNguyễn Thái Ngọc Duy, Mar 4, 2012
  34. 10/10 fsck: use streaming interface for writing lost-found blobsNguyễn Thái Ngọc Duy, Mar 4, 2012
  35. 00/11 Large blob fixesNguyễn Thái Ngọc Duy, Mar 5, 2012
  36. 01/11 Add more large blob test casesNguyễn Thái Ngọc Duy, Mar 5, 2012
  37. 02/11 streaming: make streaming-write-entry to be more reusableNguyễn Thái Ngọc Duy, Mar 5, 2012
  38. 03/11 cat-file: use streaming interface to print blobsNguyễn Thái Ngọc Duy, Mar 5, 2012
  39. 04/11 parse_object: special code path for blobs to avoid putting whole object in memoryNguyễn Thái Ngọc Duy, Mar 5, 2012
  40. Junio C HamanoMar 6, 2012
  41. 05/11 show: use streaming interface for showing blobsNguyễn Thái Ngọc Duy, Mar 5, 2012
  42. 06/11 index-pack: split second pass obj handling into own functionNguyễn Thái Ngọc Duy, Mar 5, 2012
  43. 07/11 index-pack: reduce memory usage when the pack has large blobsNguyễn Thái Ngọc Duy, Mar 5, 2012
  44. 08/11 pack-check: do not unpack blobsNguyễn Thái Ngọc Duy, Mar 5, 2012
  45. 09/11 archive: support streaming large files to a tar archiveNguyễn Thái Ngọc Duy, Mar 5, 2012
  46. Junio C HamanoMar 6, 2012
  47. 10/11 fsck: use streaming interface for writing lost-found blobsNguyễn Thái Ngọc Duy, Mar 5, 2012
  48. 11/11 update-server-info: respect core.bigfilethresholdNguyễn Thái Ngọc Duy, Mar 5, 2012

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